1. Chapter 7 The Properties of Matter

2. Objectives
SPI Recognize that all matter consists of atoms
SPI Apply an equation to determine the density of an object based on its mass and volume
SPI Distinguish between mass and weight using appropriate measuring instruments and units
SPI Determine the relationship among the mass of objects, the distance between these objects, and the amount of gravitational attraction
Define new vocabulary terms: matter, volume, meniscus, mass, weight, inertia
Describe the two properties of all matter
Identify the units used to measure volume and mass.
Compare mass and weight.
Explain how mass affects inertia.

3. Matter
Anything that has mass and takes up space
Everything has matter

4. Volume Amount of space an object takes up or occupies
All matter takes up space
No two things can occupy the same space at the same time
Measured in three dimensions

5. Measuring Liquid Volume
What tool is used to measure liquid volume?
Graduated cylinder, measuring cups, spoons, beakers
Units: Liter (L) or milliliter (mL)
Meniscus – the curve at the surface of the liquid
Measure volume at the bottom of the meniscus

6. Measuring volume of regular shaped objects
Solid objects expressed in cubic units
Cubic meters (m3)or cubic centimeters (cm3)
Volume = length x width x height
Example: What is the volume of a box that has a length of 5 cm, a width of 1 cm, and a height of 2 cm?
Step 1: Write the equation for volume
V = l x w x h
Step 2: Replace the variables with the measurements given to you and solve
V = 5 cm x 1 cm x 2 cm = 10 cm3

7. It’s Your Turn Calculate the volume for the following:
Cube with length of 5 cm
Box with height of 4 m, width of 8 cm, and length of 1 cm
Book with height of 25 cm, width of 18 cm, and length of 4 cm
CD case with 14.2 cm long, 12.4 cm wide, and 1 cm deep

8. Measuring volume of an Irregular Shaped Object
Water Displacement
Measure volume of water in graduated cylinder (initial volume)
Carefully drop irregular object into grad. cylinder
Measure the volume of the water after the water level rises (final volume)
Subtract the initial volume from the final volume
Units expressed in cm3
Solid objects are never expressed in L or mL

10. Mass Amount of matter in an object
What has more matter, an elephant or a rabbit?
The mass of an object is the same no matter where in the universe the object is.
How can you change the amount of matter in a object?

11. Weight Measure of gravitational force exerted on an object
More mass → greater gravitational force on object → greater weight
Weight changes depending on location in universe
Weigh less on moon than Earth
Weigh more on Jupiter than Earth

13. Mass vs. Weight Amount of matter
Always constant no matter where located
Measured with balance
Units: kilograms (kg), grams (g), milligrams (mg)
100g = 1N
Gravitational force on object
Varies depending on location
Measured with spring scale
Units: Newtons (N)

14. Inertia Tendency of an object to resist change in motion
Object at rest will remain at rest until something causes it to move
Object in motion will stay in motion until something causes it to stop or slow down
Object with more mass is harder to make move and harder to stop

15. Density Amount of matter in a given volume
Every object has a different density
Used to identify objects
Density is the same no matter the amount of the object
100 g of silver has a density of g/cm3
1 g of silver has a density of g/cm3
More dense → sink
Less dense → float
Density of water = 1 g/cm3
If the density of the object is less than 1 g/cm3, the object will float in water.
If density is greater than 1 g/cm3, the object will sink in water

17. Calculating Density Density = Mass Volume
Units: g cm3 or g mL or kg m3
Example: What is the density of an object whose mass is 25 g and whose volume is 10 cm3?
Step 1: Write the equation for density.
D = 𝑚 𝑣
Step 2: Replace m and V with the measurements given in the problem, and solve.
D = 25 𝑔 10 𝑐𝑚3 = 2.5 g/cm3

18. Calculating Mass and Volume
Rearrange the density equation to find mass and volume
V = 𝑚 𝐷
m = D x V
Density = Mass Volume

19. Your Turn
Find the density of a substance that has a mass of 45 kg and a volume of 40 m3.
A block of pine wood has a mass of 120 g. It has a width of 10 cm, length of 10 cm, and a height of 3 cm. What is the density of the wood? Will this block of pine float or sink in a pool of water? Why or why not?
What is the density of an object that has a mass of 350 g and a volume of 90 cm3? Will the object float or sink in water? Why or why not?
Suppose you have a lead ball whose mass is 454 g. Lead has a density of 10 g/cm3. What is the ball’s volume?
What is the mass of a 15 mL sample of mercury? The density of mercury is 13 g/cm3.

20. Objectives SPI 0807.9.1 Recognize that all matter consists of atoms
SPI Interpret the results of an investigation to determine whether a physical or chemical change has occurred
Define all new vocabulary terms: physical property, physical change, ductility, malleability, solubility, thermal conductivity, chemical property, chemical change, flammability, reactivity, precipitate.
Identify six examples of physical properties of matter.
List six examples of physical changes.
Explain what happens to matter during a physical change.
Explain two examples of chemical properties.
List 6 examples of chemical changes.
Explain what happens during a chemical change.
Distinguish between physical and chemical changes

21. Physical Properties
A characteristic that can be observed or measured without changing the matter’s identity.
Examples:
Magnetism
Heat conductivity
Strength
Flexibility
Odor
Volume
Color (sometimes)

22. Physical Properties
Thermal conductivity - rate at which substance transfers heat
Foam- poor conductor
Metal - great conductor
State – physical form in which a substance exists
Solid, liquid, gas, plasma
Density – mass per unit volume
Solubility – ability of a substance to dissolve.
Salt in water
Drink mix in water
Ductility – ability of a substance to be pulled into a wire
Copper wire
Malleability – ability of a substance to be rolled or pounded into this sheets.
Aluminum into foil

23. Physical changes
A change of matter from one form to another without a change in chemical properties.
Do not change the identity of matter involved
Examples:
Change state
Change shape
Change color (sometimes)
Freezing water
Melting a popsicle
Tearing paper
Dissolving lemonade mix in water
Sanding a piece of wood

24. Chemical Properties
The ability to change into new matter that has different properties.
Flammability – ability of a substance to burn
Burning wood
Burning a match
Reactivity – ability of two or more substances to combine and form one or more new substances.
Reactivity with oxygen – rust (iron and oxygen)
Reactivity with acid
Reactivity with base
Reactivity with light

25. Chemical Changes
A change that occurs when one or more substances change into entirely new substances with different properties.
Changes the identity of the substance
Examples:
Soured milk
Rocket blast off
Effervescent tablet dissolving in water
Statue of Liberty turning green
Burning paper
Charcoal turning to diamonds
Baking a cake

26. Signs of chemical changes
In most chemical changes, more than one sign is present.
Change in color (sometimes)
Change in odor
Production of heat
Bubbling
Fizzing or foaming
Sound or light given off
Gas given off
Precipitate formed (solid substance formed in solution)